1. Field of the Invention
The present invention relates to cameras, and more particularly, to a camera having an apparatus which is capable of setting various types of information, such as the shutter speed, the aperture value, and the ISO speed of the film, in order to take a photograph. Such a camera has the ability to automatically determine an optimum value of the particular type of information and the user taking the photograph may manually adjust a setting on the camera to a desired value, including the optimum value determined by the camera.
2. Description of the Related Art
Presently, there are cameras which have the capability of automatically determining an optimum value for various types of information for the camera, such as the shutter speed, the aperture value, and the ISO speed of the film. An automatic setting unit, such as an exposure meter or the camera CPU, determines the optimum value. In addition, a user may manually adjust the set information values relating to these types of information as desired. Different devices for manually setting information for the camera, such as the above-mentioned shutter speed, the aperture value, and the ISO speed of the film, are well known. For instance, one such device uses a dial system with a built-in board onto which surface information values are written and onto which a slidable resistor, or a 4-bit or 5-bit code value, is patterned. The dial system, positioning a click at each specified angle on an endless-type dial, increases the set information value by a given increment for each angle of rotation of the dial in a fixed direction and reduces the set information value by an equal given increment for each angle of rotation of the dial in the opposite direction. This device is disclosed in Japanese Patent Publication No. 58-63923. Also known is a 2-switch system, equipped with an up switch and a down switch, that increases the set information value by a given increment each time the up switch is pressed down, and reduces the set information value by the given increment each time the down switch is pressed down.
However, in these types of cameras, for example, during so-called manual exposure photography, in which the photographer adjusts the set information value with respect to the camera's photometric value by hand, modification of the manually set value using an information setting member when the photographer manually adjusts the set value to the optimum value can only be performed in a fixed stipulated ratio with respect to the control input, even if the present manually set value is very far from or very near to the optimum value.
In other words, for each given amount of movement by the information setting member, whether it be a given number of degrees of rotation of the information setting member or a depression of the same, the present manually set value of the information is changed by a given fixed increment no matter how far or near this presently set information value is to the optimum value (as determined by the automatic setting unit).
For this reason, when the presently set information value is very far from the optimum value, in order for the photographer to manually set the information to the optimum value, he or she has to perform a large number of control member operations, and even if the presently set information value is extremely close to the optimum value, in the case where the optimum value is in a range which is more narrow than the given fixed increment, the setting of the information could only be performed at the given fixed increment with respect to the control input of the control member, even if the photographer has modified the set information, so that there is a drawback in that the information cannot be set to the optimum value.
Therefore, in order to overcome such problems, conventionally known information setting devices for solving these types of problems are, for example, presented in Japanese Patent Publication No. 62-144147. This publication discloses a device which makes it possible for the photographer to select the incremental change of the information variation to the control input of the information setting member. Also, as described in Japanese Patent Publication No. 2-137830, there is a device in which the number of button-type information setting members is increased and the number of information variations per control is increased.
However, when information is set by these conventional setting devices, problems arise such as the tact that there is a danger of increasing the operations which change the increments of the variation in information to the control input of the control member and, therefore, the photographer may miss a shutter chance during modification of the settings, and also, when selecting the increment of the variation in information, the number of buttons may increase, thereby making control of the camera more complicated.